'Keto crotch' may be a side effect of the diet. Here's what you need to know.

People on the keto diet, a diet based around eating low-carb, high-fat foods with moderate amounts of protein, are apparently experiencing what they call "keto crotch."

This may be because drastic dietary changes can cause a pH imbalance in the vagina, according to Lisa De Fazio, a registered dietitian nutritionist.

A pH imbalance can cause "bad" bacteria to grow, causing problems like irritation and odors in the vaginal area.

The keto diet is having a moment right now. Originally developed to treat epilepsy patients who were not responsive to traditional medicine, the trending, low-carb diet aims to put the body into ketosis, a state in which it burns fat, not carbs.

Keto crotch refers to a change in vaginal odor

Since the keto diet calls for a mix of high-fat, low-carb foods with moderate proteins, it can be an adjustment for your body to get used to — and it may cause some funky side effects like a change in your vaginal odor.

Though there is no research done on the topic, the medical phenomenon may happen when you drastically change your diet by incorporating large amounts of certain macronutrients like fat and protein, according to De Fazio.

"Foods change the pH of the body. When this happens, the body will emit certain odors," De Fazio told INSIDER. "The keto diet [may] change your vaginal pH, which alters your vaginal odor — and it may not smell like roses."

So, why does all of this matter? Well, a pH imbalance can bring upon "bad" bacteria growth.

To better understand keto crotch, it's important to know how pH works

First of all, pH stands for potential of Hydrogen. It uses a number scale of zero to 14 to measure the amount of acid or alkaline of a substance.

According to De Fazio, a pH of less than seven is considered acidic and a pH of more than seven is basic.

"The pH-balance is an important factor in maintaining vaginal health," she said. "A high-fat diet, particularly saturated fat like on the keto diet, increases vaginal pH, and therefore increasing the risk of bacterial vaginosis."

A vagina should have a pH level between 3.8 and 4.5, per De Fazio. This means that it is moderately acidic. De Fazio, however, is quick to point out that what constitutes a normal pH level can vary slightly based on your stage of life.

"During your reproductive years, ages 15 to 49, your vaginal pH should be below or equal to 4.5. But, before menstruation and after menopause, a healthy pH tends to be higher than 4.5," said De Fazio. "An acidic vaginal environment is protective. It creates a barrier that prevents unhealthy bacteria and yeast from multiplying too quickly and causing infection."

A high vaginal pH level may lead to keto crotch

A high vaginal pH level might lead to a "fishy" smell. VW Pics / GettyImages

A high vaginal pH level — above 4.5 — provides the perfect environment for unhealthy bacteria to grow. It also puts you at risk for certain infections, according to De Fazio. Luckily, keto crotch can be treated and it may even go away on its own, she said.

"It may go away, otherwise you should see your OB/GYN for treatment," said De Fazio. "Your doctor may advise you to go back to a balanced diet. Any extreme changes to the body or pH is not a good idea."